説明
Design, programming, and sound is my work alone. Textures are not my work, and are not final.
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Proof of concept, working from scratch with open source tools only, including the following:
Godot Engine 4.4.1 https://godotengine.org/
func_godot https://github.com/func-godot/func_godot_plugin
Trenchbroom https://trenchbroom.github.io/